Duplexing telegraphic lines.



l. KITSEE. DUPLEXING TELEGRAPHIC LI NES.

APPLICATION FILED APR. I2. 1911- RENEWED DEC-30,1916.

1,218,870. Patented Mar. 13, 1917.

I In] GB "1 Il p @Q I WITNESSES: INVENTOR.

ISIDOR KITSEE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGN-MEN'IS, TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, OF NEW YOBK,

N. Y., A CORPORATION OF NEW YORK.

DUPLEXIN G TELEGRAPHIC LINES.

Patented Mar. 13, 1917.

Application filed April 12, 1911, Serial No. 620,649. Renewed December30, 1916. Serial No. 139,962.

To all whom it may concern:

Be it known that I, Ismon Krrsnn, citizen of the United States, residingat Philadelphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inDuplexing Telegraphic Lines, of which the following is a specification.

My invention relates to an improvement in duplexing telegraphic lines.Its object is to produce efficient means to duplex telegraph lines.

For the purpose of illustrating one form my invention may take,reference is had to the accompanying drawing.

In this drawing I have illustrated one terminal of a cable provided witha duplexing arrangement according to my invention and I have alsoillustrated in this drawing means to transmit impulses. It is obviousthat these means may vary according to requirements.

1 is the line of transmission here shown as part of a cable; 2 is theduplexing device as an entirety. This dupleXing device performs thefunction of what is known in the art as an auto-transformer, i. 6., partof the closed electric circuit is connected to the current carrying wireand part of same is connected to a circuit from which the resultantimpulses may be taken. This duplexing device comprises here the closedmagnetic circuit 3 and the closed electric circuit 4:. The closedelectric circuit consists hero of a wire wound spirally around themagnetic core and closed at its terminals.

5 is the transmitting arrangement as an entirety. This transmittingarrangement is connected through a switch or similar device 6 with thecoil 1 of the device 2 in a manner so that this connection may be variedat will. 7 is the artificial line connected through means 8 with asecond part of the coil 4. This connection is also made so as to bevaried in accordance with the desire of the operator. The line oftransmission or cable 1 is connected through means 9 with the third partof the coil l: and this connection may also be varied in accordance withrequirements.

10 is the receiving arrangement as an entirety. This receivingarrangement comprises here the relay or receiving device 11 connected tothe circuit comprising the wires 12 and 13. 14 is a condenser shunted bythe variable resistance 15 and inserted in the wire 12. The terminal ofthe wire 12 is connected through means 16 to one part of coil 4 and theterminal of the wire 13 is con nected through means 17 with a secondpart of the coil a. Both of these means are such that their relation tothe coil may be varied in accordance with requirements.

18 is an inductive resistance in shunt to the wires 12 and 18.

The function of an auto-transformer is well understood and does not needto be here referred to in particular. It suffices to say that when thehome impulses are transmitted over the line through the device 2, nocurrent will flow through the circuit 12 or 13. But when an impulsearrives from the far off station, its effect will be felt in thecircuit12 and 13 and, therefore, the relay or receiving device 11.

It is obvious that those parts of the coil d to which the receivingcircuit is connected, may be made of wire of finer gage than the otherparts; and it is also obvious that the parts to which the receivingdevice is connected may consist of a greater number of convolutions thanthe remaining parts.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is 1. As a meansto duplex lines oftransmission, an auto-transformer, part of said transformer connected tothe transmitting circuit and part of said transformer connected to thereceiving circuit comprising an impedance and a receiving deviceconnected to said impedance.

2. As a means to duplex lines of transmission, a closed electromagneticcoil, means to connect part of said coil to the transmitting circuit,part of said coil to the line of transmission and part of said coil tothe receiving circuit, said receiving circuit comprising a condenser, aresistance overbridging said condenser, and animpedance, and comprisingalso a polarized relay in shunt with said impedance.

3. In cable telegraphy, in combination with a line of transmission, anartificial line, a receiving device and a transmitting device, aduplexing device comprising an autotransformer in the form of a closedmagnetic impedance, a connection between said impedance and one terminalof said transmitting device, a connection between said impedance and oneterminal of said line of transmission, a connection between saidimpedance and one terminal of the artificial line and two connectionsbetween said impedance and the circuit including the receiving device;each of said connections comprising only part of said closed impedance.

4. In cable telegraphy, the combination with a line of transmission, anartificial line, a receiving device and a transmitting device, 01 aduplexing device comprising an autotransformer in the form of a closedimpedance, a connection between said impedance and one terminal of saidtransmitting device, a connection between said impedance and oneterminal of said line of transmission, a connection between saidimpedance and one terminal of the artificial line, and two connectionsbetween said impedance and the circuit including the receiving device,said several connections being variable to include more or less of saidclosed impedance.

In testimony whereof I aiiix my signature in presence of two witnesses.

ISIDOR KITSEE. Witnesses:

itoirn R. STILLEY, MARY B. SMITH.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

